Sewer plant receives much needed repairs

By Jeff Smith

Jerry Przybylski, public works superintendent in Keystone, shows some pumps and other aging equipment at the sewer plant on Feb. 16.

The Town of Keystone is updating some aging equipment with phase I of the sewer plant improvement project. It’s not a cheap project or a fun one.

The project has been a year in the making with working with engineers, grants being received and designs being made. It has been something that Keystone officials have wanted to do for a long time.

“It’s been awhile. It’s not something that happened overnight,” said Vanessa Row, finance officer for the Town of Keystone.

Row said sewer plants only last for so long. The sewer plant has hit the 20-year mark and it needs to be brought up to modern standards.

Jerry Przybylski, public works superintendent, said there are some things that were not designed well to start with too.

A new influent fine screen, new aeration diffusers, a new valve to isolate the cells or the water basin and two new positive displacement blowers are some of the new equipment that is being added.

Through the installation of a valve, both of the water basins can be isolated and worked on.

Przybylski said the positive displacement blowers are what creates the air that goes up into the aeration basins.

The blowers have a variable-frequency drive so they don’t have to run at a higher speed if not that much oxygen is needed, which is more cost efficient.

“The biggest cost at the sewer plant is the electricity to run those blowers,” Przybylski said.

A building at the sewer plant and the lift station will have use of clean water through the sewer system upheaval too.

UV disinfection equipment is also being replaced. 

Keystone operates an activated sludge wastewater treatment facility. Water is continually flowing at the plant.

Most of the plant operates by hand, which is different from some treatment facilities.

Advanced Engineering and Environmental Services, Inc. helped with the design and created a plan for what Keystone needed. RCS Construction of Rapid City was awarded the contract to do the work at the sewage plant.

There are two water basins there right now.

In the winter, since there is not very much human waste, food waste or other organics sent to the sewers, there is usually only one water basin running.

One of the basins right now is drained so it could be inspected.

The lift station is painted now and the valve is being put in to isolate the water basin. Crews have torn out the old UV system which is to be replaced too.

Keystone is hoping everything with the sewer improvement project will last as long as the last time the project was done.

“Some stuff goes a little longer and some stuff kind of wears out,” Przybylski said.

Everything with the project has to be done by May 1.

“This works out good for our community. We could never do this in the summertime,” Row said.

Water reuse recovery is usually at about 85 percent at the sewer plant. The oxygen, pH levels, and amount of ammonia in the wastewater are checked by a public works employee every day. Mid Continent Testing Laboratories checks the wastewater every week. The results are sent to the state and to Keystone.

There are no chemicals used at Keystone’s sewage treatment plant.

First, water is split into one of the cells then to a clarifier.The clarifier removes solids.

A UV light system is the final step in the sewage disposal system. This helps disinfect the wastewater before it goes out into the creek. UV light lamps are only used May 30 to Sept. 30.

This time of year the intake at the sewage water system is roughly 66,000 gallons a day. During the summer there is an intake of 250,000 gallons a day.

Przybylski said it’s like two different sewer plants. Like most things in Keystone, the winter is much different from the summer.

During Phase II of the sewer plant improvement plan they hope to fix some infiltration problems in town.

This is caused by defective pipe joints and broken pipes.

“Every town deals with infiltration,” Przybylski said.